What you can do here
The homepage brings together U.S. National Weather Service forecasts, current conditions, local alerts, and national outlooks. Model Lab lets you explore forecast parameters, compare models and runs at shared valid times, and export graphics with their legend, timestamps, and credits included.
Our contribution is the software and presentation around the source data: projection, map rendering, comparison alignment, playback, labeling, and the explanations in the weather guides. Agency forecasts and model fields retain their original ownership and attribution. We do not claim that a model simulation is an observation or an official warning.
Who issues the weather information?
Official agencies and model providers issue the source forecasts, observations, outlooks, and warnings. Mammatus processes and presents supported products. Our sources and methods explain which parts come from the provider and which parts Mammatus calculates. The data-source inventory gives more detail about the services used by the website and apps.
The website, Apple app, Android app, and Weather Web can differ in their available tools and coverage. Use the description of the particular product you are viewing rather than assuming every feature exists on every platform.
How we prepare explanatory content
The guides on this site are product documentation and worked examples published by Mammatus Weather. Examples identify their dates and sources. Calculators show their assumptions and do not present a numerical result as a weather forecast.
We use software to process weather feeds and may use AI-assisted writing tools when preparing documentation. Sources and worked examples are checked against the linked definitions and the actual behavior of our tools. A Mammatus organization byline identifies the responsible publisher; it does not claim a named meteorologist reviewed an article.
We welcome corrections. When a factual problem is confirmed, the affected explanation or example should be corrected and its update date changed. Reporting a data or display problem does not replace notifying the official issuer about an urgent weather concern.
Advertising and subscriptions
The website is registered with Google AdSense for advertising review, and the apps offer free and paid access. Advertising and subscriptions can support development and delivery. Advertising does not make an agency a sponsor, and paid access does not turn model guidance into an official forecast.
Our privacy policy explains advertising technologies and website data use. The terms of use describe service limitations.